That's the ideal, but the reality is that the NSA was collecting large amounts of information on
nearly all Americans for years, and the public was completely oblivious to it.
A secret court issued nearly 100% of requested warrants. Some of the warrants that have come to light were blatantly unconstitutional, but because the entire system was hidden from the public, nobody could complain. Even now, legally challenging this surveillance is almost impossible, because nobody can prove standing - the list of surveillance targets is secret after all.
The very existence of this system was secret. It wasn't democratically legitimized. Nobody voted for the system, and the voters were kept in the dark about the system's existence.
This isn't to say that China and the US are identical. They're bad in different ways. You'll be spied on in both countries, but you have legal avenues to protect yourself from imprisonment/etc. in the US. Then again, China doesn't drone strike its own citizens abroad, as far as we know.
